I recently bought a Sapphire Nitro R9 380 from Amazon and decided to fit it in myself. However I found out that I need more than I have. I need 2 PCI-E pins to actually power this beast, however my PSU only has ONE PCI-E 6+2 pin. I have tried fitting in what I have, but the graphics card works for HALF a SECOND, then powers down. What should I do?You will need to get a better power supply - Not having the suitable pins MAKES me think that it was NEVER designed to drive as high powered a card as the R9 380. Do not risk adapters, they can totally throw the load on the PSU off and damage components, not worth the risk.I am not an expert but you could try a solution I have found as useful in the past.
(***Disclaimer: I am not responsible for anything that may or may not happen to anything***)
You could connect up another psu with a pci-e and jump the green and black wires to supply the extra amperage.
Its a really good gc so I'm not sure if you'd like to try it but it could very well work that way.